Should I use rope or chain for my windows? This is a big question for a lot of homeowners, and the answer is usually very simple. If your windows originally had rope, then stay with rope and if they originally had chain, stay with the chain. The reason is not because I’m a purist, but rather a few reasons that may make more sense once I explain it a bit more.
Window pulleys are designed specifically for either chain or rope and while they can function with either, they work best with their intended material. Pulleys designed for chain have a flat wheel, whereas pulleys designed for rope have a curved wheel.
The curved wheel cradles the rope, better causing smoother operation and less stress and wear on the rope. The flat wheeled pulleys for chain give the chain a nice flat surface to ride on. When you put chain on a curved pulley, it rides mostly on the edges causing uneven wear and rougher operation.
In many ways, chain is an upgrade. It’s more attractive, longer lasting and can hold more weight than average rope, but these aren’t always a major concern and the higher cost of chain is also a factor.
Sure, chain lasts longer but good quality sash rope can last more than 60 years. That’s plenty long enough for me to not worry about replacing ropes but once in my life. Don’t get me wrong, I love the appearance of sash chain but rarely is it necessary.
Choosing the Right Rope or Chain
The first thing you need to determine is if you will be going with chain or rope, and then we can get into which size and style to choose. Like I mentioned earlier, there are pulleys that are designed to work better with chain and pulleys that are best used with rope. You can interchange them, but I would allow the type of pulley to dictate whether you should use rope or chain.
Which Rope is Right?
A lot of people worry that rope won’t be strong enough to support their heavy sash and sometimes this is a problem. How much weight can sash rope hold? The working strength of #8 Samson Spot Cord, which is what I mostly use and recommend, is 150 lbs. that means that anything less than a 300 lbs. sash (remember there are 2 ropes supporting the sash) should be just fine with this rope. Other ropes don’t have nearly the strength of Spot Cord.
Samson also makes larger sash cord in sizes #10 through #16, which can hold 480 lbs. to 1080 lbs. respectively. So, really no matter how big the sash is, you can use rope. The larger sash ropes may have trouble fitting in smaller pulleys, so it’s best to check sizes and clearances first.
If you don’t like the trademark red spot that comes on Samson Spot Cord, there are a lot of other options on the market that can work instead. The main thing in selecting sash rope is to choose a cotton rope with the proper weight rating for your sash. Synthetic ropes are not a good choice because they can stretch, causing the weights to bottom out and the sash to not stay put. Synthetic rope also does not hold up to the intense UV exposure windows are exposed to and will deteriorate faster than cotton.
Which Chain is Right?
Sizing chain for residential windows is typically #25, #8, or #829, which have a weight load of between 70 lbs. and 80 lbs. If you’re wondering what the numbers mean, I honestly don’t know as it has never been necessary for me to find out, other than to know which number is the right size chain for my windows.
Rarely is there a need for a heavier duty chain, unless you are dealing with very large commercial windows which can use #3, #35, #45. These chains have a higher weight limit between 100 lbs. and 175 lbs. and a larger diameter, so they often do not fit in standard residential pulleys, as they were intended for larger commercial applications.
The material, whether it be bronze, copper plated, stainless steel, or any other option, is less an issue of strength and more cosmetic preference. I prefer either stainless steel or solid bronze because plated chains can wear and rust with age. There are companies selling a myriad of different chain options to help you find something that suites your needs. Here are a couple places you can find quality sash chain:
Chain can be attached either simply or elegantly to sashes. It can be as simple as running the chain into the rope mortise on the side of the sash and nailing it in place. A more attractive method for attaching chain to the sash is to use chain spirals, which slot into the rope hole mortise and the chain is then thread onto the ring, just like putting keys on a key chain.
The same applies to attaching chain to the weights. You can tie a knot just like with rope or use a more attractive method of a chain hook, which attaches one side of the chain into another. You loop the chain through the eyelet on the weight and crimp it back onto itself.
I hope this has been a good primer to get you pointed in the right direction for deciding if you should be using rope or chain for your windows and where to find the good stuff. For tutorials on measuring and installing sash rope, take a look at these previous posts as well.